Wooden beam for a supporting framework and its constructional elements

ABSTRACT

A wooden beam for a supporting framework has at least two supporting members at least partially made of wood and defining together a continuous hollow cavity, and at least one shear connector located in the hollow cavity and characterized by a plurality of connection options, with the shear connector having its outside end set back with respect to an adjacent and face of the beam by a length corresponding to a forward wood length defined by a load applied to the beam.

RELATED APPLICATIONS

[0001] This application is a continuation of U.S. application Ser. No.09/341,814 filed Sep. 12, 1999.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention concerns a wooden beam for a supporting frameworkand its constructional elements, where the wooden beam consists of atleast two supporting members at least partially made of wood with acontinuous hollow space joined to form one unit, with at least one shearconnector with connection options inside the hollow space, as well asthe shear connector itself, the supporting framework that can beproduced with at least one such beam and a device for inserting at leastone shear connector into a supporting member.

[0004] 2. Description of the Prior Art

[0005] Supporting frameworks are known from many fields. Steel and 20reinforced concrete supporting framework constructions shall bementioned here only as examples and are used in various fields, fromerecting buildings to construction of bridges.

[0006] However, a disadvantage of these supporting frameworkconstructions is that they are very expensive to manufacture—forexample, assembly is commonly associated with cost-intensive weldingwork and subsequent pouring of concrete and also with regard to thenumber of different individual parts required, which must also beadapted and assembled in a complicated procedure. Furthermore, suchsupporting framework constructions can be produced only by a specialist.

[0007] Another disadvantage which should not be underestimated is thatwith the known supporting frameworks, the individual parts must beiretachably joined together and thus repeated use is out of thequestion, and whenever repairs, if any, are necessary, they can beperformed only at enormous expense.

[0008] Recently there has been a discernible trend in the constructionindustry toward increasing use of wood or wood-based materials as abuilding material in the construction of single-family dwellings.Various supporting 10 systems have been successful in this area. Solidwood, glued laminated girders and other wood-based materials as well ascross-beams are used, that are capable of absorbing and transmittinggreater forces with cross sections of the same size.

[0009] There have been various proposals for the joints to be used, inparticular in the area of the ends of these wooden constructionelements. Examples that can be mentioned here include dowels drivenacross the longitudinal axis of the beam in the area of tong-and-groovejoints, with-bolts and additional screw nails or nail connections withcover plates or tenons with cross-driven hard wood dowels or embeddedsteel T sections with dowels or tenons, in particular forked mortise andtenon joints and the like.

[0010] All these joints have the great disadvantage that the systemsconstructed with them are expensive to assemble and also require amultitude of individual parts which must also be fitted and assembled ininaccessible positions, often on site and at great effort. As a result,these systems can usually also be assembled only by expert personnel toform an overall supporting framework that can withstand forces andloads.

[0011] In addition to this trend toward increased use of wood in theconstruction industry, there is another trend in this branch of theindustry, namely that toward the construction of buildings, inparticular single-family dwellings, inexpensively through personaleffort and thus to make home ownership accessible to larger portions ofsociety. This is impossible with the known joining systems because theymust be manufactured with precision in specially equipped manufacturingsites.

[0012] Therefore, the object of this invention is to propose a beam anda supporting framework constructed with it, its 10 constructionelements, in particular shear connectors and connecting parts as well asa method of producing such beams including a device for introducing theshear connectors, which do not have the above-mentioned disadvantages,and instead they are characterized in that their elements can beassembled easily without any complicated additional measures to form asupporting framework, preferably in a detachable manner.

SUMMARY OF THE INVENTION

[0013] The feature of this invention whereby the inserted shearconnector is set back with respect to the end face of the beam, leadingto the so-called “forward wood,” causes a much more favorabledissipation of the tensile force into the ring tensile force, because itcreates a shallower force cone and a larger peripheral surface area forthe transmission of forces, while on the other hand a radially outwarddirected force component that would promote splitting is dissipated orabsorbed over a larger peripheral area.

[0014] When “wooden beams” are mentioned here, this is understood torefer to any type of wooden supporting element, including supportingelements containing wood, but preferably those suitable for joining withthe shear connectors described below. These shear connectors which aresunk in wooden beams in the manner described and claimed below arecharacterized in that they provide the possibility of connection—manydifferent embodiments are conceivable, but a standardized inside threadon the end face has proven especially advantageous—leading to a 100transmission of force between the supporting framework elements and alsopermitting a simple, time-saving and inexpensive assembly, even incombination with other materials. Additional advantages are presented inthe following description.

[0015] When a “connecting element” is mentioned below, it is understoodto refer to a spatially oriented structural part, preferably made ofmetal, in particular steels with angle-offset connection options inthree dimensions for the above-mentioned wooden beams. When a “joiningor connecting node” is mentioned below, it refers to joining multipleconnecting parts.

[0016] In a preferred embodiment, the connecting part consists of twoparallel plates lying in the main plane of the supporting framework,which also forms the floors of individual storeys of a building, forexample, namely a base plate and a top plate at a distance from it.So-called end plates are arranged between these two plates, preferablyperpendicular to them. The base plate, top plate and end plate each havedifferent connection possibilities for additional connecting elementsand/or wooden beams. These may be, for example, boreholes, which aredesigned to accommodate means for forming screw connections.

[0017] In the preferred embodiment, the end plates serve to permit aconnection between wooden beams and connecting parts and also among thedifferent connecting parts. In this way, it is possible to create asupporting framework which forms a main plane with large dimensions. Thebase plate and top plate make it possible to join the wooden beams whichform a supporting plane and run perpendicular to the main plane. Thesesupporting planes may be, for example, walls inside a building or theymay be expanded to form walls by paneling in a variety of possibleforms, while the main planes form the base of the floor for that level.

[0018] Essentially any type of detachable joint is suitable for thejoints between wooden beams and connecting parts, but screw connectionsare preferred, because the required elements are available as standardparts in any construction market and therefore special production runsare not necessary, which has a positive effect on the cost of thesupporting framework as a whole. The supporting framework according tothis invention can thus be assembled easily, even by a layperson, makingit possible for any building owner to construct his own home himself toa not insignificant extent. Only a small number of differentconstruction elements are necessary, namely, the wooden beams and meansfor producing a joint between the wooden beams and the connecting parts,with these means being integrated into the wooden beam according to thisinvention.

[0019] For such means the invention proposes a shear connector whichleads to a surprisingly simple load-bearing joint with a variety ofpossible embodiments.

[0020] The proposal according to this invention, which goes in acompletely different direction from the proposed connecting means knownin the past permits a type of “internal nailing” for the first time,opening up unforeseen possible applications. Apart from fact that thismakes it possible to shorten the connecting means that absorb theload-carrying stresses in a manner that saves on material, the novelconnection according to this invention is characterized by a simpledesign which does not require any additional securing elements.

[0021] Connecting elements for use on different construction elements,namely different in particular with regard to the shape and material,are known in various embodiments. They are especially important inparticular in construction systems which are exposed to high loads, asis the case, for example, with buildings and the like. Various types ofsupporting systems have been successful here, and must meet variousrequirements with regard to the materials used and the forces and loadsthey must withstand. This is true primarily with regard to theload-bearing capacity of the individual parts and the overallstructure—also taking into account the expediency for the overall visualimpression and details.

[0022] A typical example of the constructions discussed here would bewooden buildings, where beams or similar supporting elements are joinedtogether to form load-bearing wall, floor and/or roof supportingframeworks. Various combinations of materials can also be used, i.e.,wood as a construction material may also be combined with concrete as afilling compound or with plastic or metal parts. The material wood mayconsist of solid wood, glued laminated girders or other woodenmaterials, but solid wood in the form of round timbers, beams, squaredtimbers, boards and recently cross-beams may be used, as they arecapable of absorbing and transmitting relatively high forces incomparison with the size of their cross section.

[0023] Joints, in particular in the area of the ends of the constructionelements, have been developed and introduced into practice ‘in a varietyof forms. Here shall be mentioned only as an example a few knownpossibilities, e.g., dowels with bolts driven in across the longitudinalaxis of the beam in the area of tongue-and-groove joints and additionalscrew nails or nail connections with cover plates or tenons withcrosswise hard wood dowels or embedded steel T sections with dowels ortenons, in particular forked mortise and tenon joints and the like. Endconnections can also be achieved in a known way by means of a so-calledbeam butt joint, where the beam sides are covered with carrying parts onboth sides in the area of their ends for the transmission of force bymeans of 10 transverse dowels of a special design.

[0024] All the joints suffer from the considerable disadvantage thatsystems constructed with them are very expensive to manufacture—e.g.,due to the tenons and grooves to be molded onto the supporting parts tobe joined in the case of butt joints—and also with regard to themultitude of individual parts required, which must also be fitted andinstalled in inaccessible positions, frequently on site, in atime-consuming and expensive operation. In addition, these known joiningsystems can be implemented only in such a way that they are visible tothe outside, unless additional lamination measures are implemented inthe respective areas, e.g., in the area of the cover plates or the endfaces of the dowels.

[0025] In an attempt to at least minimize these drawbacks, there havebeen proposals for providing an end joint for the above-mentionedsupporting members, in particular of wooden beams. These include a dowelconnection which works with steel shear connectors glued into the woodenmaterials. To do so, first the end must be routed out to form acountersunk area for inserting the dowel and gluing it there, so that itcan be engaged with an appropriate attachment as a connecting means.Apart from the fact that the depth of the countersunk area and thus thelength of the dowel and thus in turn the load-bearing capacity and inparticular the tensile strength are limited because of the need forproviding a reliable adhesive layer and because of the tools and dies,the expense in the production of this joining system is notinsignificant and requires additional labor steps in the production ofthis supporting member, namely routing out a suitable bore in the endface and then gluing a suitable dowel in it.

[0026] With another known proposal, so-called shear connectors whichrequire dowels inserted across the longitudinal axis of the supportingmember are used. This known system consists of five basic elements,namely dowels, shear connector bodies, casting compound, connectingscrew and welding sleeve. This known system thus has at least thedisadvantages described above, but in addition, the filling with castingcompound and the above-mentioned visual impairment should also bementioned.

[0027] European Patent No. 159,452 A1 describes and presents node pointconnections for wooden timbers suitable for framework or latticeworkconstruction, i.e., only for tension members and compression members. Inthe state of the art, as shown by FIG. 3 in European Patent No. 159,452A1, for example, a specific recess must be created in the beam parts inan additional operation, with the length and depth being adapted to theconnecting element. In addition, special joining measures are necessaryin the end face area of the beam, but they make the force transmissionconditions complicated and unreproducible.

[0028] This invention is characterized in particular in that itselements are not visually apparent without requiring any additionalmeasures, and at the same time, the number of individual parts requiredfor this connection is minimized and the installation effort and expenseare minimized.

[0029] Advantageous embodiments of these surprisingly simple solutionconcepts are characterized in the subordinate claims. In addition to thesimplicity of the connecting systems proposed with this invention, inparticular due to the claimed installation of the new shear connector,these systems are characterized by an extraordinarily high efficiency of100%.

[0030] The term “cross-beam” as used here is understood to refer to abeam which is formed by splitting one or more tree trunks longitudinallyand turning the parts about their longitudinal axis and then joiningthese parts to form a new beam, with the curved surfaces which are thenon the inside, but originally formed the outside surface of the tree(s),forming an essentially central opening extending longitudinally throughthe cross-beam.

[0031] Through the use of a cross-beam as provided in a preferredembodiment according to the present invention, this yields surprisingadvantages, consisting in particular of the fact that in addition tosaving on wood and minimizing shrinkage cracks while at the same timeproviding a more resistant outside area, the connecting element isarranged on the inside and thus is in the plane which does not transmitforce (neutral fiber), relative to the beam, which is actually anunusual situation statically, because normally one connecting elementwould instead be provided in each of the four comers of a cross-beam,for example, as also shown by known types of cross-beam joints, but notat the center. With the joining system according to the presentinvention, the connecting element is located in an unusual plane from astatic standpoint and is thus not itself exposed to any bending forces.

[0032] In addition, this invention makes use of the fact that in apreferred embodiment a central axial recess which is present anyway witha cross-beam is utilized for insertion of the shear connector. Whenusing a glued laminated girder, for example, for the beam, at least onecontinuous groove is provided in at least one supporting member part inone additional operation according to this invention.

[0033] Depending on the dimensions and the spatial givens as well as theload requirements, various designs can be implemented, some of them withenormous advantages. This is true of the shear connector itself as wellas the supporting member, namely with regard to the shape and thematerial of which the shear connector is made and the method ofconnecting the supporting members.

[0034] Thus, in its simplest form, the core of the shear connector maybe in the shape of a rod and the mandrels may be designed with a smoothsurface. If, in another embodiment, the core is not designed to belinear but instead is wavy or undulating, this would yield an even moresecure hold, with the result that the shear connector could be keptshorter. In this sense, a further improvement can be achieved byproviding the core surface with grooving or with elevations. Variousdifferent embodiments are also possible with regard to thecross-sectional shape of the core; for example, the core may have around cross section, in particular a circular cross section, or it mayhave a polygonal cross section, in particular a square or triangularcross section.

[0035] The connection possibilities provided on at least one end of thecore can also be designed in many conceivable ways, but an inside threadon the end of at least one end of the core has proven to be especiallyadvantageous. For example, a threaded stem or the like may be screwedinto this inside thread, and it may also have connecting elements on itsfree end, or it may be designed as a hook, ball, knob, eyelet or thelike. It is also possible within the scope of this invention to providean outside thread at the end of the core or to have a threaded pin witha smaller diameter than the diameter of the core molded onto the end. Inaddition, the shear connector may be inserted into a constructionelement to be joined to at least one other construction part, optionallyalso extending crosswise through the beam.

[0036] In the simplest embodiment, the mandrels are joined in one piecewith the core, and they may be distributed uniformly or irregularly onthe outside surface of the core. Different variants are also possiblewith regard to their axial orientation, depending on the givenrequirements, but with regard to the method of inserting the shearconnectors into the supporting member to be described in detail below,it has proven advantageous in the manufacture of the joining system tohave the axes of the mandrels run perpendicular to the longitudinal axisof the core, in particular with half the number of mandrels running inone direction and the other half running in the opposite direction.

[0037] If the mandrels are oriented in parallel to one another, thisyields the advantage that for insertion (pressing) of the shearconnector into the supporting member, the force to be applied may berelatively low. The mandrels may be arranged in parallel rows on theoutside surface of the core along its longitudinal axis, with themandrels of one row being offset to the mandrels of at least oneadjacent parallel row.

[0038] The number of rows of mandrels pointing in each of the twodirections indicated above can be varied as needed, but four rowspointing in one direction have proven advantageous with a diamond-shapedcross section or in particular a square cross section of the core, againwith two rows on each of the side faces of the square. In addition, therows of mandrels may run straight and parallel to the longitudinal axisof the core, but they may also run diagonally to it.

[0039] As mentioned above, in the simplest embodiment, the mandrels havea smooth surface; however, the surface may also have steps, with atleast one undercut on each mandrel, the undercut being designed toencircle the mandrel. However, the surface may be designed like a drillnail, having a peripheral ridge, in particular in the form of a spiral,or it may have a sawtooth shape.

[0040] The mandrels are preferably joined in one piece with the core,which is the case in particular when the shear connector is produced bycasting iron, annealed cast iron, cast steel, brass or aluminum, forexample; production from ceramics is also possible. The shear connectoraccording to this invention may also be made of sheet metal. On thewhole, suitable production methods include in particular pressing,stamping, compression molding, edging, nibbling, milling, lathing and/orsuitable shaping methods, depending on the material and requirements.

[0041] As mentioned above, the shear connector according to thisinvention makes possible a joining system with which it is possible tocreate a connection of supporting members at the end faces. The more orless internal nailing of the shear connector in the supporting member asmentioned in this connection is achieved by the fact that the shearconnector(s) is or are inserted or impressed or forced into thesupporting member. The supporting members in question are thus designedso that they consist of multiple component elements, as is the case withthe so-called cross-beams, for example, which are glued together frompreferably four beam quarters cut to size with a specific orientation ofthe annual rings to one another, in a manner with which those skilled inthe art are familiar, to thereby achieve an especially greatload-bearing capacity.

[0042] Although this invention is characterized by great advantages, inparticular when using cross-beams, other glued wooden constructionelements such as standard beams, glued laminated girders and the likeinto which the shear connectors are pressed in the proper positionduring the manufacturing process. In the case of the use of thisinvention with plastic and/or concrete girders, which is also possible,the shear connector is preferably cast into it.

[0043] When the terms “beams” or “girders” are used here, this isunderstood to refer to any type of supporting member which is intendedfor a composite joint.

[0044] Various positions are possible for the orientation and positionof the shear connectors; in the normal case, each beam will receive oneshear connector at each end. For shorter beams or with a transverseinsertion of the shear connectors in the beam, which is also possible,the shear connector(s) may extend throughout the entire length orthickness of the beam. A shear connector extending crosswise through thebeam is also recommended at points of intersection, where one or moreother beams, each of which is joined at the end to the shear connectorarranged at the point of intersection, are connected.

[0045] The setback position of the shear connector according to thisinvention results in a so-called “forward wood” which further increasesthe effect achieved with the shear connector, i.e., effectively securingit to prevent it from being pulled out, and at the same time creating abetter distribution of the reactive forces in the area of the ends ofthe girder in a load case, thus creating optimum connections.

[0046] Depending on the load case, the shear connector(s) lie(s) in atleast one plane of symmetry; however, they may also be arranged in thetension zone at a sufficient distance from the side faces of the beam.In addition, an arrangement of several shear connectors one above theother, preferably in a parallel alignment, is also possible toadvantage.

[0047] As mentioned above, the joining system according to thisinvention is suitable for a variety of constructions, such as wood-wood,wood-steel and/or wood-steel-concrete constructions, and also, ofcourse, in combination with plastic as a supporting member and in othercombinations of materials of such construction elements of compositematerials in addition to those listed above.

[0048] With this invention, which leads to 100% efficiency intransmission of forces, a considerable volume of wood is spared in aneconomical and advantageous manner, because the dimensions and crosssections of the woods used in the respective constructions can now bekept thinner. In addition, assembly of the constructions—even in thecombination of different materials—is very simple and can beaccomplished in a time-saving manner. Thus, this eliminates the need forlarge and expensive hoists and cranes, which are necessary withconstructions using wooden beams, for example, because now due to theirthinner design they can be lifted and installed by two workers. Due toits simple design, the production of the shear connector according tothis invention is also inexpensive and can also be accomplishedindustrially as mass-produced articles.

[0049] Building constructions which could previously be implemented onlyat considerable expense, often with great difficult, can now beimplemented more easily and inexpensively due to the high efficiency ofthe joining system according to this invention, and these constructionscan also be implemented in other shapes that could not previously beachieved. Insertion of the shear connector during the productionprocess—gluing and then pressing the individual beam pieces—can beaccomplished with extreme dimensional accuracy and with visualobservation, which is not the case with the above-mentioned proposalsfor joining ends as discussed above, because with them, the dowel orshear connector must be inserted into a predrilled blind hole where novisual observation is possible and then must be glued or cross-doweled,again without visual observation. On the other hand, the beam parts withthe present invention are glued together to form a complete beam so thatinsertion of the shear connector which has previously been dipped inglue is performed in an intermediate stage, e.g., when the two lowerhalves of a cross-beam are glued, at which point the shear connector canthen be positioned accurately, optionally reproducibly with the help ofsimple laser techniques, even with millimeter precision. As soon as theshear connector has been inserted appropriately, receiving holes for themandrels of the shear connectors can be predrilled to fix theirpositions, although this is not absolutely necessary; then the upperbeam part, which is in turn composed of two wooden beam parts previouslyglued together in the case of a cross-beam, is pressed onto the gluedsurface of the lower beam half, while the shear connector mandrels areinserted or pressed into the upper and lower parts of the beam at thesame time; in the case of prepressing the shear connector into the lowerhalf of the beam, which is also, possible, this is then pressed to thefinal depth into the lower beam half during the final gluing. It is thusclear that in contrast with the state of the art, practically no time isrequired for inserting the shear connector according to this invention.

[0050] As shown by the preceding discussion, cross-beams are excellentlysuited for the joining system according to this invention, because theyhave an internal hollow channel into which the shear connector core canbe inserted optimally due to the course of the external annual ringsbecause of the way in which they are joined.

[0051] This also greatly simplifies the logistics in shipping andconveyance, because large-scale constructions need no longer be preparedin the plant, but instead due to the use of the shear connectoraccording to this invention, the individual parts can be screwedtogether at the construction site with dimensional accuracy and thusshipping costs can be saved due to the fact that shipping is greatlyfacilitated.

[0052] Due to the reliable 100% transmission of force, the staticcalculations can also be performed more easily and can be typed moreeasily with regard to the use of certain materials and the dimensions tobe provided, and thus specific statics can also be created more easilyand thus less expensively.

[0053] Ultimately, these advantages will also benefit the buildingowner, in particular in the case of homeowners, not only from thestandpoint of production costs, but also because of the possibility ofutilizing simple joining systems to the extent that some of the work, ifnot all the related work can be performed on one's own initiative.

[0054] Finally, the above-mentioned advantages also open up new areas ofuse of the joining system according to this invention, e.g., in bridgebuilding in addition to the above-mentioned applications.

[0055] The present invention also includes an economical method ofproducing the supporting members provided with such a connectingelement, and it should be emphasized here that this method is by nomeans limited to shear connector of the type described above, butinstead is also suitable for introducing other types of anchoring orconnecting elements. The basic concept of a suitable device forperforming this method is given in claim 97 with embodiments accordingto the following claims.

[0056] With a surprising and advantageous effect, this invention makesuse of the fact that in many cases supporting members are composed ofmultiple parts, as is the case with cross-beams, for example, which areassembled in a known manner from multiple “trunk parts” with a specificalignment of the fiber, preferably glued together and characterized byespecially good load-bearing properties. According to this invention,the insertion of the connecting element is incorporated into the processof assembling the parts of the supporting members. However, it is alsopossible to apply this invention to other supporting members such asglued laminated girders and also one-piece girders, but the latter wouldthen first have to be broken down into component elements to be able toproceed then according to the present invention.

[0057] Cross-beams are especially suitable for the present inventionbecause due to their special method of manufacturing, they have acentral recess which, in an advantageous embodiment of this invention,can be utilized for the insertion of the connecting elements, inparticular when it is a shear connector according to the type claimedhere. When using other supporting members, appropriate recesses mustfirst be introduced without any significant deleterious effect on theexcellent properties of the supporting framework to be produced with thehelp of the shear connector according to this invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The present invention is described in greater detail below on thebasis of the accompanying drawings, which illustrate some preferredpossible embodiments, showing:

[0059]FIG. 1 two connecting parts with boreholes as connecting options;

[0060]FIG. 2 the connection of four connecting parts with wooden beamsattached to them, pointing in three different directions;

[0061]FIG. 3 a detail of an overall supporting framework with apronounced, relatively large main plane, e.g., one storey;

[0062]FIG. 4 a perspective view of a supporting framework with 10 twomain planes, e.g., of a storey;

[0063]FIG. 5 a top view of a shear connector;

[0064]FIG. 6 the lower half of a cross-beam interrupted in the middlelongitudinally and glued together;

[0065]FIG. 7 the cross-beam part according to FIG. 6 with one shearconnector inserted at each end;

[0066]FIG. 8 another step in the joining system manufacturing process,specifically just before joining the two glued cross-beam halves;

[0067]FIG. 9 the finished cross-beam with the shear connectors insertedand connection options at the ends;

[0068]FIG. 10 a diagram corresponding to FIG. 8 on the example of aglued laminated girder;

[0069]FIG. 11 an installation situation where the shear connectors havebeen inserted outside the longitudinal middle axis (asymmetrically withthe cross section of the beam);

[0070]FIG. 12 an exploded diagram of a relatively shot cross-beam with acontinuous shear connector, in a sectional diagram not showing the“forward wood”;

[0071]FIGS. 13a through 13 e various cross-sectional shapes of the shearconnector cores;

[0072]FIG. 14 a perspective diagram of a connecting node with two pairsof cross-beams (shown cut off) held at an angle to one another, witheach pair consisting, of two cross-beams placed together with one shearconnector each;

[0073]FIG. 15 a top view of an installation shown schematically;

[0074]FIG. 16 part of a joining station of an inclined feed as part ofthe installation according to FIG. 1;

[0075]FIGS. 17a and b details of the inclined feed for shear connectors;and

[0076]FIG. 18 a cross-sectional view of the joining station.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0077]FIG. 1 shows two connecting parts 1, each composed of a hexagonalbase plate 2 and a parallel hexagonal top plate 3. Five rectangular endplates 4-1 through 4-5 are perpendicular to and connected to each baseplate 1 to whose free upper end edges top plate 3 is fixedly connected.These plates are preferably made of steel and are welded together.

[0078] As FIG. 1 also shows, base plate 2, top plate 3 and end plates4-1 through 4-5 each have boreholes 5 which serve to detachably attach aconnecting part 1 either to one or more additional connecting parts 1 toform a connecting node—this would be possible here by means of endplates 4-1 and 4-5, for example—or they offer the possibility ofproviding a connection for additional supporting framework members.

[0079]FIG. 2 shows some details of the assembly of supporting frameworkmembers of a supporting and load-bearing construction, where fourconnecting parts 1 are linked by their end plates 4-1 and 4-5 so thatbase plates 2 and top plates 3 point in the same direction, and endplates 4-2, 4-3 and 4-4 offer possible connections for wooden beam 6,which then form the main load-bearing plane and run parallel to baseplate 2 and top plate 3. Then only a suitable paneling is necessary tocreate the floor of a 10 storey, for example.

[0080] The end plates 4-2, 4-3 and 4-4 are arranged so that the woodenbeams 6 detachably attached to them by screws, for example, each form anangle of 45°. End plates 4-1 and 4-5 are each perpendicular to plates4-2 and 4-4.

[0081] In the case illustrated in FIG. 2, with base plate 2 facing downand top plate 3 facing up, four wooden beams 6 are each mounted at aright angle to one another in the main plane on the end faces ofconnecting elements 1. The connection between connecting node 1 andwooden beams 6 has been established by means of the shear connectors 13proposed according to the present invention (shown as an example in FIG.5). These shear connectors permit an extremely simple method of joiningof wooden beam 6 to the connecting parts 1 without any negative visualeffect on the finished supporting framework due to visible extraelements. Details on the shear connector and possibilities of itsinstallation are described below.

[0082] Wooden beams 7 are mounted on the top plates 3 of the connectingparts 1, and are aligned perpendicular to the wooden beams 6 forming themain planes and they form the supporting planes. The connection betweenthe wooden beams 35 7 and the connecting node are explained here in thesame way as described above.

[0083]FIG. 3 shows a detail of an overall supporting framework, havingconnecting parts 1 with boreholes 5 in its corner areas which faceoutward, permitting attachment of any desired supporting frameworkelements and thus continued construction of the supporting framework inany conceivable manner and direction. The main plane of the supportingframework is formed by a central connecting node composed of fourconnecting parts 1 whose base plates 2 face down and whose top plates 3face up and by four wooden beams 6, each at a right angle to the otherand arranged in a star on the connecting node. Wooden beams 6 aremounted on the connecting node in the same way as already described inconjunction with FIG. 2, namely by the end plate 4-3 of the individualconnecting elements 1. At the other end of wooden beam 6, which is thesame length, a connecting part 1 is mounted by way of end plates 4-3.Additional wooden beams 8 are also connected to these outer connectingparts 1 by way of end plates 4-2 and 4-4, so that the beams 8 join twoconnecting parts 1 that are on the outside, thus forming a square as themain plane.

[0084] Wooden beams 9 facing downward are mounted on the base plates 2of the outer connecting parts 1, so that the main plane can be supportedon them. The wooden beams 9 form the supporting planes arrangedperpendicular to the main plane.

[0085]FIG. 4 shows a completed embodiment of a supporting framework,whereby in contrast with the embodiment according to FIG. 3, the mainplanes are formed from beams 6 running parallel to one another. Two mainplanes run more or less side by side in each stage, so that when thereare two adjacent planes, two connecting parts 1 are joined together intheir opposing corner areas in the manner illustrated here—with anallocation like that shown in FIG. 1—which shows clearly that thissystem can be expanded at will without requiring any renovation. Theadvantage of this embodiment is, among other things, the fact that therespective ceiling construction is produced with parallel ceiling beams,requiring on the one hand only a very simple cutting operation and alsoon the other hand permitting uniform paneling.

[0086] Of course, reinforcing beams which run diagonally can also beused in the supporting planes with suitably oriented connecting parts.

[0087] Sheets, for example, can be mounted on the wooden beams 6 of themain plane; top plates 3 of the connecting elements 1 offer connectionoptions facing upward for this purpose. The same thing is also true ofany partitions in the supporting planes of the supporting framework.

[0088] The top plates and base plates thus represent excellent bearingsurfaces for any assembly variation, greatly facilitating assembly,which ultimately requires only screw connections, which can be performedwithout any expert knowledge.

[0089]FIG. 5 shows a shear connector 13 according to this invention,namely in the embodiment with an octagonal core cross section and withmandrels 14 and 14 a arranged in parallel rows with an offset. Therecess at the end in the form of an inside thread 16 is also shown withdotted lines.

[0090]FIG. 6 shows the lower half 11 of a cross-beam—interrupted in themiddle part to permit a shortened representation—consisting of twopartial beam pieces 11 a and 11 b joined together and glued. The patternof annular rings at the end is diagramed schematically. A groove-likechannel 12 is formed due to the special method of joining the individualpartial pieces 11 a and 11 b which have been cut to size.

[0091] According to FIG. 7, two shear connector 13 according to thisinvention are inserted into this channel 12 at each end of the lowerbeam halves 11 in the embodiment shown here, namely with parallel andperpendicular mandrels 14 on the shear connector core 15 in theembodiment shown here, said core also being provided with a centralrecess 16 at the end and set back with respect to the beam end face,thus creating the so-called “forward wood” A at both ends. In thepreceding part of the description, it was explained in detail how theindividual parts of the shear connector 13 according to this inventionmay be designed and implemented.

[0092] Then in the remaining course of the process of producing thebeam, an upper cross-beam half 17 consisting of two partial beam pieces17 a and 17 b is assembled and glued and then, according to FIG. 8,pressed from above onto the lower cross-beam half 11 prepared accordingto FIG. 7 and glued to it, with the mandrels 14 pressed or forced intothe upper cross-beam half 7 (the “antipodes” of the mandrels havingalready been pressed into the lower cross-beam half 11 in thisrepresentation). As mentioned above, it is advisable to predrill thebeam halves according to the pattern of shear connector mandrels.

[0093] After the end of the pressing and gluing operation, this yieldsthe joining system according to this invention as illustrated in FIG. 9,where the two shear connectors 13 at the end have been shown visibly forthe purpose of illustration. Moreover, FIG. 9 shows one possibility foran end connection to the shear connectors 13 in the form of ahexagonal-head screw 18 screwed into the recess 16, which has beenprovided with an inside thread. As already explained elsewhere,modifications of the end of the shear connector itself as well as theconnecting elements optionally to be mounted on it. In particular, eachshear connector may optionally be provided with a continuous insidethread running perpendicular to the longitudinal axis, which thenpermits additional directionally modifiable connecting options, e.g., inthe form of threaded spindles running obliquely and/or transversally.

[0094]FIGS. 10 and 11 show an additional possible application of thepresent invention, namely on the example of a glued laminated girder 11,17, which must first also be provided with the channel 12, which ispresent anyway in the cross-beam, by means of corresponding cutting andmachining methods before insertion of shear connector 13. Otherwise, themeasures described previously for producing the finished beam 11/17 areapplicable accordingly, with the difference in comparison with thecross-beam being that the two beam halves 11 and 17 are constructed inlayers in the case of the glued laminated girder.

[0095]FIG. 11 shows another variant, where the shear connectors 13 arearranged not symmetrically in the beam cross section but instead arearranged eccentrically, which can prove to be advantageous in certainload cases, because then the shear connectors 13 can be placed in thetension zone, depending on the load situation, so that there can be acorresponding influence on the connecting point to dissipate thesupporting forces.

[0096]FIG. 12 shows a relatively short cross-beam 11/17 shortly beforecompletion of the joining system, provided with a continuous shearconnector 13, but to simplify the diagram, only one row of mandrels 14is shown completely, as in FIGS. 7, 8 and 9 discussed above, and the“forward wood” is not shown at all, and also for reasons of simplicity,only a few mandrels 14 a are shown of the row on the adjacent inclinedface (the core of the shear connector shown here has a square crosssection).

[0097]FIG. 13 shows a few possible core cross sections, namely FIG. 13ashowing a square core cross section 15 a, and FIG. 13b showingschematically the insertion into a beam 11/17 in an end view.

[0098]FIG. 13c shows an octagonal cross section 15 b, while FIG. 13dshows an annular cross section 15 c, and FIG. 13e shows a triangularcross section 15 d. In all the end views in FIG. 13, the possibleconnection to the shear connector 13 is indicated in the form of aninside thread 16.

[0099] In addition, FIG. 13 shows one possibility of parallelorientation of the mandrels 14, namely half of them perpendicularlyupward and the other half of them perpendicularly downward in theopposite direction, and in this case the pressing forces required tojoin the two beam halves run in the direction of the longitudinal axisof the mandrels 14. The triangular shape according to FIG. 13 can berecommended in particular, where the lower half of 20 the beam isdesigned flat on the glued face. Of course, however, mandrels 14pointing downward may also be provided with a triangular cross section.

[0100]FIG. 14 shows especially impressively the enormous possiblevariations according to this invention on the example of a special nodepoint, with four cross-beams 11/17 being joined together by a connectingpart 1 according to this invention, two of them being oriented inparallel and one on top of the other, with the two pairs 30 running atright angles to one another, as is typically the case in the corner areaof a ceiling (see also FIG. 4). The shear connector 13—connectors areprovided in each beam in the manner described above—are shown projectingbeyond the end face of the beams in the embodiment shown 35 here for thepurpose of illustration; in practical use, the beams would of course bemuch longer, and the connectors at the end would be designed so thatthey can be attached to appropriate connecting parts 1 merely byscrewing the thread heads or screws and nuts 18 tightly; due to the typeof perspective diagram selected here, the connection of beams 11/17 toconnecting part 1 which is performed in this manner in the embodimentillustrated in FIG. 14 is not visible, but it should be readily apparentin particular taking into account the diagrams in FIGS. 1 as well as 9and 12.

[0101]FIG. 14 also illustrates the particular advantage of theconnecting parts 1 according to the present invention which is derivedfrom the fact that the base plate 2 projects beyond the top plate 3 atthe side, so that this creates a supporting surface and at the same timecreates the stop face for the connected girder or beam 11/17, which inturn at least partially absorbs the reactive forces for relieving theload on the shear connectors and on the other hand at least supports, ifnot guarantees, an aligned orientation at the proper angle, so that evena layperson can construct a building with accurate angles withoutcomplicated plumbing of the perpendicular and handling of water levelsin an extremely short period of time comparatively.

[0102] On the example of just some of the possible embodiments, thedrawings illustrate, first, the simple design and, secondly, theextremely favorable and time-saving creation of the joining system, butit should be emphasized here again that, as explained in the precedingdescription of the figures, many different modifications, are possiblewithout going beyond the scope of the present invention.

[0103]FIG. 15 shows a preferred possibility of an installation forcarrying out the process according to this invention, consistingessentially of the following parts or stations:

[0104] a planing line consisting of a planing installation 21 with afeed 22 and a delivery 23;

[0105] a package feed 25 for the press line 26;

[0106] a continuous microwave oven 27;

[0107] a gluing station 28;

[0108] a transfer and joining station 29;

[0109] a press station 211;

[0110] a glue cleaning station 212;

[0111] and a downstream depositing or delivering station 213.

[0112] The method of introducing at least one connecting element into asupporting member is carried as explained below on the example of ashear connector 214 inserted into a cross-beam 215.

[0113] The starting material for the cross-beams 215 is wooden boardshaving different cross-sectional dimensions, which are first planed inplaning line 24 on all sides, then chamfered in appropriate locationsand next cut at the center. The resulting cross-beams 125 may have anydesired cross-sectional area. The resulting “quartered timbers” 216 arethen removed from the production installation illustrated in FIG. 16 andsent to a drilling station 30 (not shown).

[0114] At this station, drilled holes are created in the insides 217 ofthe quartered timbers of cross-beam 215 so that the resulting pattern ofdrilled holes corresponds to the mandrel pattern of shear connector 214.These drilled holes may be provided at any desired location along thequartered timbers 216, but are preferably at one end a distance awayfrom the end face of the beam, thus forming the “forward wood” in theend product, which increases the effect achieved with the shearconnector, i.e., effectively securing it against extraction andoptimizing the force cone.

[0115] Although it is also possible to press the shear connector 214into the prepared quartered timbers 216 without first drilling a hole,inserting the shear connector into a corresponding pattern of holesoffers the advantage that the wood fibers are not split, more fiber isin contact with the mandrels and thus the load-bearing capacity of thesupporting members is increased considerably, e.g., by approximately25%.

[0116] The quartered timbers 216 are then supplied over receptacle 25 topressing line 26, where they are first heated in a continuous microwaveoven 27—temperatures of approximately 90° C. to 100° C. have provenespecially advantageous. Due to this heating, the subsequent gluingoperation can be shortened considerably.

[0117] On the way to the gluing station 28, the quartered timbers 216are moistened along the subsequent glue joints 218 and then glue isapplied in gluing station 28. The glue is applied by means of rotatingnozzles, which permit accurate metering by varying the rotational speedand the distance from the surface of the wood.

[0118] In the transfer and joining station 29, four quartered timbers216 pretreated and drilled with holes according to the precedingdiscussion and at least one shear connector 214 are joined to form across-beam 215 having at least one connecting element. This can even bedone by hand, with the two lower quartered timbers 216 a, 216 b beingplaced in a blank mold (not shown), the shear connectors 214 beingdipped in a glue pot and inserted into the hole pattern(s) of the lowerquartered timbers 216 a, 216 b. Then the similarly pretreated anddrilled upper quartered timbers 216 c, 216 d are placed on the lowerquartered timbers 216 a, 216 b including the shear connector(s) 214 withan accurate fit, with the pattern(s) of drilled holes provided therematching the mandrel pattern of the shear connector(s). The shearconnector 214 can of course also be inserted by machine, as explainedbelow on the basis of FIGS. 16, 17a, b and 19.

[0119]FIG. 16 shows the joining station 29 in a schematic perspectiveside view. This station consists of a feed chute 219 which according toFIG. 17 runs at an angle of 45° to the bottom for reasons to beexplained below, and its grating-like bottom is itself formed bymultiple round rods 220 running in the feed direction with a spacebetween them. This type of feed has been selected for the preferred casewhen shear connector 214 consists of a core 221 with projecting mandrels222, which then grip between the rods in the manner illustrated in FIG.17b and thus are guided securely. The inclined position of the feedchute 219 is derived from the fact that a support and alignment are thusachieved here on the example of a shear connector 214 with a core 221having a square cross section, so that the 25 mandrels 222 which arelater to be inserted into the hole pattern in the quartered timbers 216of the supporting members then extend in the direction of the drilledhole.

[0120] In addition to the above-mentioned feed chute 219, the joiningstation 29 includes a repeating device 223, indicated by a double arrowA, which works together with a stamp unit 224 (see FIG. 16). Stamp unit224 includes a stamp 225 which can move vertically up and down in theembodiment illustrated here and whose lower free end face has thenegative profile of shear connector 214. Repeating device 223 is inparallel alignment on the lower end of feed chute 219. In operation, itgrips the shear connectors 214 individually and transfers them to thearea below the stamp 225, which accommodates the shear connectors 214 ina frictionally engaged manner due to clamping devices 226 arrangedlaterally on its end faces. These clamping devices 226 are designed sothat they either engage in recesses there or reach around projectingareas located there, depending on the design of the end faces of theshear connectors 214. As also shown in FIG. 16, each shear connector 214remains in the angular position determined by feed chute 219 during thistransfer, i.e., aligned vertically with mandrels 222.

[0121] The stamp 225 then travels down, so that at least one shearconnector 214 is inserted with its mandrels 222 into the 15 pattern ofholes in the lower cross-beam half 216 a, 216 b produced from twoquartered timbers 216 a and 216 b.

[0122] This device is adjusted so that the stamp 225 travels only untilit is in contact with the upper end face of the lower beam half 216 a,216 b, i.e., to the extent that the mandrels 222 20 are insertedcompletely into the material, but there can be no destruction due to thecore 221 being pressed into the material of the beam. Thus, due to themutual allocation and interaction of the feed chute 219, the repeatingdevice 223 and the stamp unit 224, an accurate alignment and centeringof the shear connectors 214 relative to the lower beam half 216 a, 216 bis guaranteed.

[0123] The process sequence according to this invention can also becarried out without predrilling holes in the quartered timbers 216—ifthe connecting elements 214 are to be inserted into a supporting membermade of a softer material than the connecting elements 214 themselves.In this case, the stamp 225 must be dimensioned so that the mandrels 222can be inserted into quartered timbers 216.

[0124] The additional function of the automatic joining station 29according to FIG. 16, which is implemented here in multiple stages andis integrated into the overall process, is derived from therepresentation in FIG. 18. In the embodiment illustrated here, thejoining station 29 consists of two main areas which are formed by apivoting and/or rotating longitudinal path and receptacle 227 and aswivel receptacle 228. For this multiple-stage joining station 29,multiple feed chutes 219 (magazines) and stamp units 224 distributed inthe longitudinal direction may be provided, which permits economicalproduction of multiple 10 supporting members at the same time.Therefore, the quartered timbers 216 are processed to yield a lengthsuch that several supporting members 215 are formed from them by cuttingthe assembled and glued timbers across the longitudinal axis. The shearconnectors 214 are arranged so they are distributed over the length sothat after cutting, there is one shear connector 214 in or near each endarea of the individual supporting members 215.

[0125] The one pivotable longitudinal receptacle 227 of the joiningstation 29 consists of a cross 231 which can rotate about a longitudinalaxis 229 and preferably has four receptacle quadrants 232 a, b, c, d.

[0126] According to the diagram in FIG. 18, the above-mentionedinsertion of shear connector 214 into lower cross-beam part 216 a, 216b, which is prefabricated to this extent, takes place in the upper rightquadrant 232 a. The quartered timbers 216 a, 216 b may already be gluedand pressed (curing of glue under pressure). The lower cross-beam part216 a, 216 b is held in position by a pressure cylinder 233 at the side.

[0127] As soon as the shear connector(s) 214 has/have been inserted intothe lower beam half 216 a, 216 b, the rotating cross 231 is rotated 90°counterclockwise (see curved arrow B) until reaching the positionillustrated in the upper left quadrant 232 b. At this time, an “upper”beam half 216 c, 216 d assembled in a manner similar to that describedfor the lower beam half 216 a, 216 b and optionally also glued andpressed is guided by the left swivel receptacle 228, which is alignedparallel to rotating cross 231, so that it is brought into the positionshown in the middle part of FIG. 18 by an appropriate clockwiseswivelling motion (curved arrow C) about the axis of rotation 234, sothat the two beam halves 216 a, b and 216 c, d are opposite one anotherin a horizontal plane. The upper beam half 216 c, 216 d is pressed in ahorizontal direction against the lower beam half 216 a, b by means ofanother pressure cylinder 235 which is fixedly connected to the leftswivel receptacle 228 and thus also executes the swivelling motions,whereby a plate 236 which is adjustable according to double arrow D isprovided on the left swivel receptacle 228 in order to permit adjustmentof the various beam dimensions. By operating the pressure cylinder 235,the “upper” beam half 216 c, d is pushed to the right onto the lowerbeam half as far as the two end faces 237 on both sides, so that theprojecting mandrels 222 of the shear connector(s) 214 are then alsoinserted into the upper beam half 216 c, d, or if there is no existingpattern of holes, the mandrels are pressed into the material. The beamsurfaces 237 which are to be brought in contact are coated with glue.

[0128] The U-shaped swivel receptacle 228 on the left, whose one side isformed by adjustable plate 236, is then swivelled 90° counterclockwise(curved arrow C) about its axis of rotation 234, thus achieving theupright position shown in the left part of FIG. 18. This also showsclearly that the pressure cylinder 235 also executes the swivellingmotion.

[0129] After being assembled, the complete wooden beam 215 with theshear connector 214 inserted is automatically lifted into a press wherethe beams are glued. In the embodiment described here, the completewooden beam 215 with the shear connector 214 inserted is automaticallylifted into a press where the beams are glued. In the embodimentdescribed here, the gluing is performed in 5-minute cycles at pressuresof up to 210 bar. If no continuous microwave oven 27 is provided in theproduction line, a longer pressing operation is necessary, which can becarried out in special pressing stations that accommodate multiplebeams.

[0130] After gluing, the cross-beams 215 are also cleaned in a gluecleaning device 212.

[0131] It has proven to be especially advantageous to produce cross-beamparts 215 with a length of one meter and with a shear connector 214inserted at one end, and then two of these cross-beam parts can beassembled subsequently to form a supporting member of any desired lengthwith connection options on each side; this is performed on a jointinginstallation by inserting a cross-beam intermediate piece of any desiredlength, having no shear connector 214. It is also possible to insert twointermediate pieces, i.e., to perform three jointing steps. Essentiallybeams up to 12 meters long can be produced in this way, with a crosssection of 10×10 cm, 10×20 cm or 12×24 cm, for example.

[0132] After the final curing of the adhesive, any desired known furtherprocessing steps are possible, such as planing or chamfering or othermachining operations or preparation for 30 assembly.

[0133] The installation described above with its process stepsrepresents only one possibility of manufacturing the beams according tothis invention. In particular, parts may be omitted, supplemented,replaced and/or combined to form new manufacturing lines, adapted to thegiven conditions.

[0134] The following procesz steps are essential for the shear connectortechnology according to this invention:

[0135] In particular, cross-beam quartered timbers or cross-beam halves,which were previously glued together from two cross-beam quarteredtimbers and have already been hollowed out accurately to the requireddimensions and coated with glue, are predrilled at defined locations ina CNC-controlled automatic drilling machine according to the shearconnector mandrel pattern in an accurate manner.

[0136] The cross-beam quartered timbers or halves, preferably precut onone side to approximately the finished length and precut on the otherside to exactly the finished length preferably pass through a gluingstation, downstream from which the shear connectors which have beendipped in glue are inserted into the pattern of holes.

[0137] In the press, the cross-beams with the shear connectors alreadyinserted are glued and then cut or trimmed accurately to the exactfinished dimension. After this process, a fine planing of the outsidesurfaces is performed. It is found that with an optimum arrangement ofsuccessive production steps, the final processing steps are limited toaccurate trimming of the wooden beams and the final all-round planing ofthe finished cross-beam.

[0138] Use of glued laminated girders is also possible, in which caseseveral shear connectors may also be inserted into a beam one above theother due to the sandwich structure, like the design of severalcross-beams, each provided with a shear connector and arranged one abovethe other (see FIG. 14).

[0139] This opens up numerous possible variations, including theconstruction of cross-beams with internal shear connectors, such thatthe cross-beams not only have a dimensional stability comparable to thatof steel structures but they are actually superior with regard to fireprevention. Due to the above-mentioned accurate determination of theposition of the shear connector in the longitudinal axis in combinationwith the very accurate determination of the cross-beam opening which isnow possible, this creates a satisfactory possibility of connection tostructural parts that are essentially in terms of the statics, e.g., tosteel node points according to this invention.

What is claimed is:
 1. A wooden beam, comprising at least two supportingmembers at least partially made of wood and defining together acontinuous hollow cavity; and at least one shear connector located inthe hollow cavity and characterized by a plurality of connectionoptions, the shear connector having an outside end thereof set back withrespect to an adjacent end face of the beam by a length corresponding toa forward wood length defined by a load applied to the beam.
 2. A woodenbeam according to claim 1, comprising two shear connectors located inthe hollow cavity and arranged at opposite ends of the beam,respectively.
 3. A wooden beam according to claim 1, wherein the atleast one shear connector extends substantially throughout an entirelength of the beam.
 4. A wooden beam according to claim 2, furthercomprising a rod arranged in a center of the beam end linking the twoshear connectors.
 5. A wooden beam according to claim 1, wherein the atleast one shear connector is located in the tension zone.
 6. A woodenbeam according to claim 1, wherein the two shear connectors lie in atleast one plane of symmetry.
 7. A wooden beam according to claim 2,wherein the two shear connectors lie symmetrically with respect to eachother.
 8. A wooden beam according to claim 2, wherein the two shearconnectors are arranged parallel to each other.
 9. A wooden beamaccording to claim 1, wherein the beam is formed as a cross-beam.
 10. Awooden beam according to claim 1, wherein the beam is formed as a gluedlaminated girder.
 11. A wooden beam according to clam 1, wherein theshear connector has at least one of an inside thread and an outsidethread.
 12. A wooden beam according to claim 1, wherein the shearconnector provides for connection options in three direction withrespect to an axis of the wooden beam.
 13. A wooden beam according toclaim 1, wherein the shear connector comprises a core, and a pluralityof mandrels projecting therefrom, and has at least one connection optionin an area of at least one end of the core.
 14. A wooden beam accordingto claim 13, wherein the core has a shape of a rod.
 15. A wooden beamaccording to claim 13, wherein the core is straight.
 16. A wooden beamaccording to claim 13, wherein the core has a circular cross-section.17. A wooden beam according to claim 13, wherein the core has apolygonal cross section.
 18. A wooden beam according to claim 13,wherein the core has a triangular cross section.
 19. A wooden beamaccording to claim 13, wherein the core has a corrugated surface.
 20. Awooden beam according to claim 13, wherein the mandrels are formed aselevations.
 21. A wooden beam according to claim 13, wherein the corehas an inside thread on at least one end thereof.
 22. A wooden beamaccording to claim 13, wherein the core has an inside thread, runningacross a longitudinal axis of the core.
 23. A wooden beam according toclaim 13, wherein the mandrels are joined in one piece to the corner.24. A wooden beam according to claim 13, wherein the mandrels arealigned parallel to one another.
 25. A wooden beam according to claim13, wherein the mandrel axes run perpendicular to a longitudinal axis ofthe core.
 26. A wooden beam according to claim 13, wherein half of anumber of mandrels point in one direction and another half of the numberof mandrels point in an opposite direction.
 27. A wooden beam accordingto claim 13, wherein the mandrels are distributed uniformly over anoutside surface of the core.
 28. A wooden beam according to claim 13,wherein the mandrels are distributed randomly over an outside surface ofthe core.
 29. A wooden beam according to claim 13, wherein the mandrelsare arranged in parallel rows on an outside surface of the core.
 30. Awooden beam according to claim 29, wherein the mandrels of one row areoffset relative to the mandrels of at least one adjacent parallel row.31. A wooden beam according to claim 29, wherein four rows of mandrelsface in one direction.
 32. A wooden beam according to claim 29, whereinthe rows of mandrels run in straight lines parallel to a longitudinalaxis of the core.
 33. A wooden beam according to claim 29, wherein therows of mandrels run diagonally with respect to each other.
 34. A woodenbeam according to claim 29, wherein the rows of mandrels have a graduatesurface.
 35. A wooden beam according to claim 13, wherein each mandrelhas at least one undercut.
 36. A wooden beam according to claim 35,wherein the undercut encircles the mandrel.
 37. A wooden beam accordingto claim 13, wherein each mandrel has a spiral peripheral ridge on asurface of each mandrel.
 38. A wooden beam according to claim 13,wherein each mandrel has a sawtooth surface.
 39. A wooden beam accordingto claim 13, wherein the shear connector is formed of a materialselected from a group containing iron, cast iron, cast steel, brassaluminum, ceramic, and sheet metal.
 40. A method of producing a woodenbeam having at least two supporting members at least partially made ofwood and defining together a continuous hollow cavity, and at least oneshear connector located in the hollow cavity and characterized by aplurality of connection options, the shear connector having an outsideend thereof set back with upset to an adjacent end face of the beam, themethod comprising the steps of: forming two supporting members; formingat least one groove-shaped channel in at least one of the two supportingmembers; inserting a shear connector in the groove-shaped channel sothat an outer end of the shear connector is spaced inward from an endface of the at least one supporting member by a length corresponding toa “forward wood” length; and connecting the two supporting memberstogether with the shear connector.
 41. A method according to claim 40,wherein the shear connector is inserted into the groove-shaped channeland is, during the manufacturing of the beam, at least one of pressedthereinto and glued therein.
 42. A method according to claim 40, whereinthe beam is formed of four supporting members.
 43. A method according toclaim 40, wherein all of the four supporting members have a samecross-section.
 44. A method according to claim 40, wherein the beam isformed as one of a cross-beam and a glued laminated girder.
 45. A methodaccording to claim 42, comprising the steps of forming at least onegroove-shaped channel in each of the two supporting members, inserting ashear connector, which is formed of a core with mandrels projectingtherefrom, in each of the groove-shaped channels, and connecting thefour supporting members with the two shear connectors.
 46. A methodaccording to claim 40, further comprising the step of providing a shearconnector formed of a core with a plurality of mandrels projectingtherefrom, and forming in the at least one of the two supporting membersa plurality of boreholes arranged in a pattern corresponding to apattern of mandrels provided in the shear connector and receivable inthe boreholes formed in the at least one of the two supporting members.47. A method according to claim 45, comprising the steps of forming, inanother of the two supporting members, a plurality of boreholes arrangedin a pattern corresponding to the pattern of respective mandrelsprovided on the shear connector, and wherein the inserting stepcomprises placing the shear connector in the groove-shaped channel withthe respective mandrels being inserted in the boreholes formed in the atleast one supporting member, and the connecting step comprisesconnecting the two supporting members by inserting free-standingmandrels into the boreholes formed in the another of the two supportingmembers.
 48. A method according to claim 40, comprising the steps ofproviding the shear connector formed of a core and a plurality ofmandrels projecting therefrom, and wherein the inserting step includesplacing the shear connector in the at least one groove-shaped channelformed in the at least one of the two supporting members, and whereinthe connecting step comprises pressing the mandrels into the at leastone of the two supporting members and pressing remaining free-standingmandrels into another of the two supporting members.
 49. A methodaccording to claim 40, wherein the two supporting member are heatedbefore being connected.
 50. A method according to claim 40, comprisingthe step of at least one of moistening and gluing the two supportingmember to each other and the shear connector.
 51. A method according toclaim 49, wherein glue is being cured under pressure.
 52. A methodaccording to claim 40, wherein the groove-shaped channel-forming stepcomprises forming the channel with a cross-section corresponding to thecross-section of the shear connector.
 53. A method of forming a beamhaving a predetermined length, comprising the steps of forming aplurality of beam elements having a predetermined length and having eachat least two supporting members at least partially made of wood anddefining together a continuous hollow cavity and characterized by aplurality of connecting options, the shear connector having an outsideend thereof set back with respect to an adjacent end face of a beamelement; and connecting the beam elements with each other, forming thebeam.
 54. A method according to claim 52, comprising the step ofinserting at least one intermediate piece having a predetermined lengthbetween two adjacent beam elements.
 55. A method according to claim 53,wherein the intermediate piece has at opposite longitudinal ends thereofat least one of bores and joint fingers cooperating with respectivejoint fingers and bores provided at end faces of the adjacent beamelements.